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(No Model.) 3 sneetsshe'et 1.

J. U'. ELWOOD.

TRACK BRAKE.

No. 688,858. Pa'ggnted Aug. 24,1 97;

' I v r'1 IIVVEIVTOB WITNESSES i Mia,

I ATTORNEYS.

(No Model.) 3 SheetsQSheet 2. J. U. ELWOOD.

TRACK BI iAKE.

- No. 588,858. Patented Aug; 24,1897. k

. INVENTOR WITNESSES k Arm/mm.

J; U ELWOOD. TRACK BRAKE.

" 3 Sheets-Sheet 31 (No Model.)

No. 588,858. Patented Au 24, 1897.

INVENTR 24 M nrromrs.

JEFFERSON U. ELWOOD,- OF MOKEESPORT, PENNSYLVANIA, ASSIGNOR T HIMSELF AND DUANE SMITH, OF SAME PLACE.

TRACK-BRAKE.

SPECIFICATION forming part of Letters Patent No. 588,858, dated August 24, 1897.

7 Application filed November 6, 1896. Serial No. 611,208. (No model.)

To all whom itmay concern;

Be it known that I, JEFFERSON U. ELWOOD,

track-brakes, particularly to those shown in my former patents, No. 544,574, of August 13,

1895, and No. 561,502, of 'June 2,1896.

Reference is to be had to the accompanying drawings, forminga part of this specification,

in which similar characters of reference indicate corresponding parts'in all the figures.

Figure 1 is a side elevation of the brakeshoe and its immediate operating mechanism. Fig. 2 is a top plan view of the same. Fig. 3 is a side elevation, on a larger scale, of the same in connection with the power mechanism for operating it. Fig. 4 is a top plan View of the shoe and its i n mediately-connected mechanism. Fig. 5 is a section through the same, taken across the car. Fig. 6 is a top plan view of the latch for use in connection with the quick-release mechanism. Fig. 7 is an elevation ofa portion of the power mechanism for operating the brake. Fig. 8 is a section taken through the slide carrying the shoe upon the line 1 1 of Fig. 9. Fig. 9 is a longitudinal section through the shoe and the lower end of the slide carrying the same, and Fig. 10 is a section taken on the line 2 2 of Fig. 9.

The object of my invention is to provide a' shoe for track-brakes which will have a greater holding power than the ordinary shoe and to provide a more efficient mechanism for applying power to the same. The shoe is shown in detail in Figs. 8, 9, and 10. The shoe consists of the casting A, rounded at each end and fiat on the bottom, adapted to bear upon the upper surface of the rail. This is attached by means of the lug A to the sliding member B. The lower end of this slide B is recessed to receive the upper portion of the shoe. It also has a hole, through which passes the lug A upon the upper side of the shoe. The upper end of this lug projects into a lateral opening B in the slide sufficiently so that a pin a may be inserted through a hole in the lug and thus fasten the shoe in place.

which will have a greater holding effect upon the surface of the rail than will cast-iron. This may be emery, carborundum, clay, lead, or any substance-having this quality.

, The slide B is given a vertical movement by means similar to those used in the patents referred to. The'slide is mounted so as to have-a vertical motion in the ways 0 upon the bracket 0, which is fastened to a horizontal bar 0 of the framework. To the slide B is attached a link E, and this in turn by the vpin D to one end of abell-crank lever D. This lever is pivoted at'Dto the bracket 0. Its upper end is connected by the pinD with a rod F, 'which'leads to the power mechanism. f .To insure. the prompt raising of the slide B and shoe A, I have provided a pin 0 upon the rear thereof and have connected to this I a spring 0, which at the upper end is connected, by means of the bolt'O to the frame or a portion of the bracket. 1 This is in tension when the shoe is down, and as soon as the power is removed therefrom the spring will quickly raise the shoe.

The mechanism for applying power to the brake consists of a vertical staff or shaft J, mounted in bearings on the end of the car and provided with a step-bearing J to prevent the motion of the shaft in one direction. This shaft carries a worm I, engaging with a 0 worm-wheel H, which latteris mounted upon a pivot h in a bracket H, which is fastened to the floor of the car. Attached to the worm-wheel H and revolving therewith is the cam G. This cam is in general of a spiral character-that is, with a varying radius. It is grooved upon its periphery and adapted to receive a chain F. The end of this chain is attached to the cam at G or near the point where it is of the greatest radius.

The position shown in Fig. 3 is the position I when the shoe is elevated and the brakes rebrake.

leased. In this position the crank-arm tor operating the chain is the greatest and the this radius becomes smaller, thus giving less 1 motion and greater power. The chain F is attached to the rod F, and thus acts upon the To secure a quick release of the brake, I. have provided the following means: To the staff J, just above the car-'fioor,is fixed a collar K, which has a spiral cam-surface K upon the lower end thereof. This is adapted to engage the upper surface .of the latch L. (Shown in plan view in Fig. 6..) This latch is pivoted at ,L to one side of the staif J and has a sloping surface L matching with the .slopingsurface Kof the collar K. This latch is adapted to he engaged by the footof the j motorman and thrown over, so that .the surface L of the latch will engage the cam-.snr- 1 face on the collar K. As thes-haft is revolved this will cause the shaft to :be lifted .suffb; ciently to disengage the worm I from the wheel Hand the wheel H maythen fly back- 1 ward, releasing the :hralce. Aslight projeci tion L placed upon .the floorof thecanser-ves 3 to hold the latch .in disengaged position, but

does not prevent its being raised over the same by the foot .of the motorman. III the,

drawings 1 havesho-wn but one trackbnahe 1 upon each side .of the .caroperated from opposite-ends. -I have found this :toxbesnfiieient forall ordinary purposes. Itis veryevfliident, 1

however, that the number of these .brakesor 1 shoes may be increased whenever desired, 1

using the connecting-levers in common use for such purpose.

The-device herein described is one which ,givesgreat power in the application of the brake, a rapid movement at the beginning of l the application, witha decrease inthe :speed, but an increase in power for the latter portion of the application. iLt also provides: means for a quick release.

Having thus described my invention, 31: .claimes new and desire "to secure Letters Patent- 1. A shoe fora track-brake havingdove-i tailed or inwardly-expanding recesses in its undersu-rface, said recesses being filled with a material, the blocks of which maybe molded in place and have a higher frictional resistance than the body of the shoe, a perforated lug upon the upper side of the shoe, a slide carrying the shoe and having a hole for said 'ilug and an intersecting hole exposing the perforation in the lug and a key adapted to fit the perforation in the lug and lock the shoe "in place, substantially as described.

2. In a vehicle-brake, the combination of the brake-shoe and a flexible connector for operating the same, with a pivoted cam having a variable radius which decreases as the brake is tightened and to which the flexible connector is attached, a worm-wheel attached to said earn, a wormengaging therewith, and .a hand-wheel and shaft carrying said worm, and means .by which the worm may .be quickly disengaged from thegear, substantially .asdescribed.

3. In a vehicle-brake, the combination of the brake-shoe and a flexible connector for operatingthe same, with a pivoted cam having .a variable radius which decreases .as the brake'is tighte ed and to which the flexible .connectoris attached, means for rotatingthe same, and means by which the worm may be quickly disengaged trom the gear, substantially as described.

4.. An operating mechanism :fora Sbrake, comprising .a worm and worm-gear, .an endfaced cam .sunrcundin g the worm-.shafuoperating means attached to said shaft, and a movable latch adapted to be moved so as 1.0 engage said -end-faced cam, snhstantial lyas escribed.

5. An operating mechanism for a hrake, comprising a w-cnma-nd worm-gear, a grooved cam of decreasing radius attached to the worm-gear, a flexible connector attached to said cam and operating the brake-.shoaan end-faced .cam surrounding the worm-shaft, operating means attached tosaid shaft, .and :a movable latchadapted to be moved so as to (engage said en -faced cam, substantially as JEFFERSON ELWOQD. Witnesses;

H). GARDNER, .J. WALL-1e.

2 describe 

